title: First characterization of bacterial pathogen, Vibrio alginolyticus, for Porites andrewsi White syndrome in the South China Sea.
abstract: BACKGROUND
  White syndrome, a term for scleractinian coral disease with progressive tissue loss, is known to cause depressed growth and increased morality of coral reefs in the major oceans around the world, and the occurrence of this disease has been frequently reported in the past few decades. Investigations during April to September in both 2010 and 2011 identified widespread Porites andrewsi White syndrome (PAWS) in Xisha Archipelago, South China Sea. However, the causes and etiology of PAWS have been unknown.
  
  
  RESULTS
  A transmission experiment was performed on P. andrewsi in the Qilianyu Subgroup (QLY). The results showed that there was a significant (P ≤ 0.05) difference between test and control groups after 28 days if the invalid replicates were excluded. Rates of tissue loss ranged from 0.90-10.76 cm(2) d(-1) with a mean of 5.40 ± 3.34 cm(2) d(-1) (mean ± SD). Bacterial strains were isolated from the PAWS corals at the disease outbreak sites in QLY of the Xisha Archipelago, South China Sea, and included in laboratory-based infection trials to satisfy Koch's postulates for establishing causality. Following exposure to bacterial concentrations of 10(5) cells mL(-1), the infected colonies exhibited similar signs to those observed in the field. Using phylogenetic 16S rRNA gene analysis, classical phenotypic trait comparison, Biolog automatic identification system, MALDI-TOF mass spectrometry and MALDI Biotyper method, two pathogenic strains were identified as Vibrio alginolyticus .
  
  
  CONCLUSIONS
  This is the first report of V. alginolyticus as a pathogenic agent of PAWS in the South China Sea. Our results point out an urgent need to develop sensitive detection methods for V. alginolyticus virulence strains and robust diagnostics for coral disease caused by this and Vibrio pathogenic bacterium in the South China Sea.
authors.affiliation: Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, Hainan University, Haikou, P R China ; Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, P R China.
authors.forename: Xie
authors.initials: X
authors.lastname: Zhenyu
authors.forename: Ke
authors.initials: K
authors.lastname: Shaowen
authors.forename: Hu
authors.initials: H
authors.lastname: Chaoqun
authors.forename: Zhu
authors.initials: Z
authors.lastname: Zhixiong
authors.forename: Wang
authors.initials: W
authors.lastname: Shifeng
authors.forename: Zhou
authors.initials: Z
authors.lastname: Yongcan
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000382:microbiology*; D001483:Base Sequence; D002681:China; D017931:DNA Primers / Q000235:genetics; D018562:Disease Transmission, Infectious; D008969:Molecular Sequence Data; D009792:Oceans and Seas; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D044149:Vibrio alginolyticus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D014774:Virulence
chemical_list: D017931:DNA Primers; D012336:RNA, Ribosomal, 16S